Foaming cartridges, pumps, refill units, and foam dispensers using the same

ABSTRACT

An exemplary foam cartridge for a foam pump includes a housing having an inner diameter, a first foaming stage disposed within the housing, and a second foaming stage disposed within the housing. The first foaming stage is spaced apart from the second foaming stage. The first foaming stage has at least two different types of mix media, and the second foaming stage has at least two different types of mix media.

RELATED APPLICATIONS

This application This application claims priority to and the benefits ofU.S. Non-Provisional Application Ser. No. 62/192,837, filed on Jul. 15,2015 and titled IMPROVED FOAMING CARTRIDGES, PUMPS, REFILL UNITS, ANDFOAM DISPENSERS USING THE SAME, and which is incorporated herein byreference in its entirety.

TECHNICAL FIELD

The present invention relates generally to foam pumps, refill units forfoam dispensers, and foam dispenser systems, and more particularly tofoam pumps, refill units, and foam dispensers having an improved foamcartridge.

BACKGROUND OF THE INVENTION

Liquid dispenser systems, such as liquid soap and sanitizer dispensers,provide a user with a predetermined amount of liquid upon actuation ofthe dispenser. In addition, it is sometimes desirable to dispense theliquid in the form of foam by, for example, injecting air into theliquid to create a foamy mixture of liquid and air bubbles. Someliquids, such as, for example, alcohol-based liquids are difficult tofoam and require enhanced mixing. Pumps for generating foam may form thefoam by pumping a liquid and air mixture through a foam cartridge. Priorfoam pumps and foam cartridges are disclosed in U.S. Published PatentApplication No. 2014/0054323 filed on Mar. 9, 2013 and entitledHorizontal Pumps, Refill Units and Foam Dispensers with Integral AirCompressors, U.S. Pat. No. 8,955,718 filed on Mar. 18, 2013 and entitledFoam Pumps with Lost Motion and Adjustable Output Foam Pumps, U.S. Pat.No. 8,763,863 filed on Jul. 3, 2013 and entitled Bifurcated Foam Pump,Dispensers, and Refill Units, and U.S. Pat. No. 7,850,049 filed on Jan.24, 2008 and entitled Foam Pump with Improved Piston Structure, all ofwhich are incorporated herein by reference in their entirety.

SUMMARY

Exemplary embodiments of foam dispensers, refill units for foamdispensers, and foam cartridges are disclosed herein. An exemplary foamcartridge for a foam pump includes a housing having an inner diameter, afirst foaming stage disposed within the housing, and a second foamingstage disposed within the housing. The first foaming stage is spacedapart from the second foaming stage. The first foaming stage has atleast two different types of mix media, and the second foaming stage hasat least two different types of mix media.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the present invention willbecome better understood with regard to the following description andaccompanying drawings in which:

FIG. 1 is a cross-section of an exemplary dispenser having a refillunit;

FIG. 2 is a cross-section of a foam pump of an exemplary dispenser andrefill unit; and

FIG. 3 is a cross-section of an exemplary foam cartridge.

DETAILED DESCRIPTION

FIG. 1 illustrates an exemplary embodiment of a foam dispenser 100. Thecross-section of FIG. 1 is taken through the housing 102 to show a foampump 120 with a foaming outlet portion 130, a container 116, and anactuator 140. The dispenser 100 includes a disposable refill unit 110.The disposable refill unit 110 includes the container 116, foam pump120, and foaming outlet portion 130. The dispenser 100 may be awall-mounted system, a counter-mounted system, an un-mounted portablesystem movable from place to place, or any other kind of dispensersystem.

The container 116 forms a liquid reservoir that contains a supply ofdispensable foamable liquid within the disposable refill unit 110. Invarious embodiments, the contained liquid could be for example asanitizer, a cleanser, a disinfectant, or some other dispensable liquid.In the exemplary disposable refill unit 110, the container 116 is acollapsible container and can be made of thin plastic or a flexiblebag-like material. In other embodiments, the container 116 may be anon-collapsible container and can be made with, for example, a thickerplastic than its collapsible counterpart. A non-collapsing containerusually includes a vent (not shown) to vent the container.

The container 116 may advantageously be refillable, replaceable or bothrefillable and replaceable. In the event the liquid stored in thecontainer 116 of the installed disposable refill unit 110 runs out, orthe installed refill unit 110 otherwise has a failure, the installedrefill unit 110 may be removed from the dispenser 100. The empty orfailed disposable refill unit 110 may then be replaced with a newdisposable refill unit 110. The refill unit 110 may be secured withinthe dispenser 100 by any means, such as, for example, a releasablelocking mechanism, a quarter turn connection, a threaded connection, aflange and fastener connection, a clamped connection, or any otherreusable connection.

The refill unit 110 includes foam pump 120 that is in fluidcommunication with the container 116. The foam pump 120 may be securedto the container 116 by any means, such as, for example, a threadedconnection, a welded connection, a quarter turn connection, a snap fitconnection, a clamp connection, a flange and fastener connection, or thelike. The foam pump 120 pumps liquid and air through a foaming outletportion to dispense rich foam at the outlet nozzle 134 of the pump.

The foam pump 120 is generically illustrated because there are manydifferent kinds of foam pumps which may be employed in dispenser 100.For example, the foam pump disclosed in U.S. Published PatentApplication No. 2014/0367419 filed on Jun. 13, 2004 and entitled FoamCartridges, Pumps, Refill Units And Foam Dispensers Utilizing the Sameand U.S. Pat. No. 8,272,539 filed on Dec. 3, 2008 and entitled AngledSlot Foam Dispenser, which are incorporated by reference in theirentirety, may be used in dispenser 100.

In one embodiment, air and liquid pumps of the foam pump 120 areenclosed within a pump housing 121. In one other embodiment, the foampump 120 includes separate air and liquid pumps. In this embodiment, theliquid pump and air pump may both be part of the refill unit 110. Inother embodiments, the liquid pump may be part of the refill unit 110and may be disposed of upon depletion of the liquid from the container116, while the air pump (not shown) may be attached to the dispenser 100and is not disposed. The concept of having a foam pump that has a liquidpump portion separable from an air pump portion may be referred to as a“split pump” shown and described in U.S. Pat. No. 8,763,863 filed onJul. 3, 2013 and entitled Bifurcated Foam Pump, Dispensers, and RefillUnits which is incorporated herein in its entirety.

The foaming outlet 130 is in fluid communication with the premix chamber122 of the foam pump 120. Foaming media 132 are retained within thefoaming outlet 130. The foaming media 132 generates foam from anyfoamable liquid. Some embodiments are especially well suited forenhanced foaming of foamable liquids containing alcohol. For example,the foaming media 132 is longer than prior foam cartridges and includesmultiple spaced apart foaming stages (See FIGS. 2, 3) that generate richfoam. In some embodiments the foam is generated at increased actuationspeeds and pressures.

Dispenser 100 contains one or more actuators 140. As used herein,actuator or actuating members or mechanism includes one or more partsthat cause the dispenser 100 to move liquid, air and/or foam.

Actuator 140 is generically illustrated because there are many differentkinds of pump actuators which may be employed in dispenser 100. Actuator140 of dispenser 100 may be any type of actuator, such as a manuallever, a manual pull bar, a manual push bar, a manual rotatable crank,an electrically activated actuator or other means for actuating foampump 120, which may include one or both of a liquid pump portion and anair pump portion. Electronic actuators may additionally include a sensor(not shown) to provide for a hands-free dispenser system with touchlessoperation

During operation of the dispenser 100, liquid is drawn in from thecontainer 116 by the foam pump 120 through a liquid inlet 126 and pumpedinto premix chamber 122. Simultaneously, air is drawn into the foam pump120 through an air inlet 124 and is pumped into the premix chamber 122to mix with the liquid. The air and liquid mixture is forced through thefoaming media 132 in the foaming outlet portion 130 to dispense richfoam from the outlet nozzle 134. The foaming media 132 includes twofoaming stages that each include a combination of at least two mixmedias that generate high quality foam, such as, for example, screens,porous members, sponges, baffles, or the like. An aperture 115 in abottom plate 103 of the housing 102 allows foam dispensed from thenozzle 126 to exit the housing 102 for use by the user.

FIG. 2 illustrates an exemplary embodiment of a foam dispenser 200 thatincludes a foam pump 230 attached to a container 212 to form anexemplary refill unit 210. Foamable liquid is stored in the container212 and is combined with air in the foam pump 230 to create rich foamthat is dispensed from a pump outlet 227. In the illustrated embodiment,foam pump 230 includes a piston pump with liquid and air chambers thatare actuated simultaneously when the pump 230 is actuated. The foam pump230 may be any kind of pump, however, suitable for pumping and mixingliquid and air to create foam.

The interior of the container 212 forms a reservoir 220 for holdingfoamable liquid. A neck 214 of the container 212 is received within acollar 238 of the foam pump 230. In the illustrated embodiment, thecontainer 212 is secured to the foam pump 230 with a threadedconnection, but the container 212 can be secured to the foam pump 230 byany means, such as, for example, a snap fit connection, a friction fitconnection, a quarter turn connection, a flange and fastener connection,a clamped connection, or the like (A one-time connection would actuallybe preferred).

The foam pump 230 includes a pump housing 231, a piston assembly 240, afoaming outlet 260, and a spring 241. The pump housing 231 includes anannular outer housing 232, an annular inner housing 234, an end cap 236,and the collar 238. The end cap 236 of the pump housing 231 is disposedproximate the container and forms a closed end of the annular outer andinner housings 232, 234. The piston assembly 240 includes a piston body242, an outer bore 243, an inner piston body 244, an inner bore 245, anoutlet portion 246, and an outlet bore 247. In the illustratedembodiment, the inner piston body 244 is shown as a separate component,though it may be formed integrally as part of the piston body 242. Thespring 241 engages a shoulder 248 on the interior of the pump outletportion 246 of the piston assembly 240 and the interior of the end cap238 of the pump housing 231.

The pump housing 231 and piston assembly 240 form a cylindrical liquidpump chamber 222 and an annular air pump chamber 224. The liquid pumpchamber 222 is formed at least in part by the inner annular housing 234,the end cap 236, and the inner piston body 244. The air pump chamber 224is formed at least in part by the annular outer housing 232, the end cap236, the piston body 242, and the outer bore 243. The central bore 245encloses a premix chamber 226. A liquid pump inlet 221 in the end cap236 is in fluid communication with the reservoir 220 and the liquid pumpchamber 222. A liquid pump outlet 223 is in fluid communication with theliquid pump chamber 222 and the premix chamber 226. An aperture 225places the air pump chamber 224 in fluid communication with the premixchamber 226. The pump outlet portion 246 and foaming outlet 260 form apump outlet 227 that is in fluid communication with the premix chamber226 and the atmosphere.

The piston assembly 240 slideably engages the pump housing 231. Movementof the piston 240 within the housing 231 between charged and dischargedstates causes the volume of the liquid and air pump chambers 222, 224 toexpand and contract. The piston 240 may be actuated manually or by anactuator. As used herein, actuator or actuating members or mechanismincludes one or more parts that cause the dispenser 200 to move liquid,air or foam. Upward actuation of the piston 240 moves the piston 240from the charged state to the discharged state, compressing the spring241. When the upward actuation force is removed, the spring 241 movesthe piston 240 back to the charged state, expanding the liquid and airchambers 222, 224 thereby charging the pump 230. The piston 240 may bemoved by any means, such as, for example, by use of an electricactuator, a mechanical actuator, a pneumatic actuator, or the like.

The annular air pump chamber 224 is larger in volume than thecylindrical liquid pump chamber 222. Thus, actuation of the piston 240pumps a larger volume of air than liquid through the foam pump 230.Adjusting the dimensions, for example, the diameter, of the air andliquid pump chambers 224, 222 allows the ratio of the flow rate of airto liquid to be adjusted. The air flow rate may be, for example, betweenabout one and about twenty times the liquid flow rate, and preferablyabout ten times the liquid flow rate.

A liquid inlet valve 250 is disposed in the liquid inlet 221 of the endcap 236 of the pump housing 231. The liquid inlet valve 250 is a one-wayvalve that is oriented such that it allows flow into, and prevents flowout of, the liquid pump chamber 222 through the liquid pump inlet 221. Aliquid outlet valve 252 is disposed at the end of the inner piston body244. The liquid outlet valve 252 is a one-way valve that is orientedsuch that it allows flow out of, and prevents flow into, the liquid pumpchamber 222 through the liquid pump outlet 223. In some embodiments,liquid inlet and outlet valves 250, 252 can be any kind of one-wayvalves, such as ball and spring valves, wiper valves, poppet valves,flapper valves, umbrella valves, slit valves, mushroom valves, duck billvalves, or the like.

A liquid pump seal 254 on the inner piston body 244 seals against theinner pump housing 234 to prevent liquid from leaking out of the liquidpump chamber 222 during charging and discharging of the pump 230. Theliquid pump seal 254 is illustrated as an integrally molded wiper seal,but may be any kind of suitable seal, such as, for example, an o-ring oran elastomeric washer.

An air pump seal 256 on the piston body 242 seals against the outer pumphousing 232. The air pump seal 256 seals the air pump chamber 224 duringthe discharging actuation cycle, but allows air to enter the air pumpchamber 224 during the charging cycle. The air pump seal 256, therefore,operates as a one-way valve that is oriented such that it allows airflow into, and prevents flow out of, the air pump chamber 224. In someother embodiments, the foam pump 230 may include a separate one-way airinlet valve (not shown) fluidly connecting the air pump chamber 224 tothe atmosphere. The air pump seal 256 in an embodiment that includes aseparate one-way air inlet valve (not shown) can be any suitable seal,such as, for example, an O-ring, an elastomeric washer, an integrallymolded wiper seal, or a lubricant, such as, for example, grease.

The foaming outlet 260 attaches to the outlet portion 246 of the pistonassembly 240 and includes a central bore 264 in fluid communication withthe outlet bore 247 that together form the pump outlet 227. A nozzle 262of the foaming outlet 260 allows foam generated in the foaming outlet260 to be dispensed to the user. The foaming outlet 260 may be securedto the piston body 240 by any means, such as, for example, a quarterturn connection, a flange and fastener connection, a clamped connection,a friction fit connection, or the like. In some embodiments, the foamingoutlet 260 may be welded or glued to the piston body 240, or may beformed integrally with the piston body 240.

A foaming cartridge 270 comprising a first foaming media 272 and asecond foaming media 274 is retained within the pump outlet 227. Each ofthe first and second foaming stages 272, 274 include a combination of atleast two mix medias, such as a combination of at least two of thefollowing: screens, porous members, sponges, baffles, or the like. Thefirst and second foaming stages 272, 274 are separated by a gap 276. Insome embodiments the gap is approximately equal to about 10% to about50% of the interior diameter of the pump outlet 227.

A dust cap 280 attaches to the pump housing 230 to conceal and protectoutlet portion of the dispenser 200 and is removed prior to installingrefill unit 210 in the dispenser 200.

During operation of the dispenser 200, the piston assembly 240 of thefoam pump 230 is moved by the spring 241 from a discharged to a chargedposition. Foamable liquid flows from the reservoir 220 through theliquid pump inlet 221 and liquid pump inlet valve 250 into the liquidpump chamber 222 as the liquid pump chamber 222 expands. Simultaneously,air flows into the air pump chamber 224 through the air pump chamberseal 256. When the dispenser 200 is actuated, the piston 240 is movedfrom the charged to discharged position, forcing liquid out of theliquid pump chamber 222 through the liquid pump outlet valve 252 andliquid pump outlet 223 into the premix chamber 226. Simultaneously, airis forced out of air pump chamber 224 through the aperture 225 and intothe premix chamber 226 to mix with the foamable liquid. The air andliquid mixture in the premix chamber 226 flows out of the premix chamber226 and through the foam cartridge 270 to generate rich foam at the pumpoutlet 227.

The dispenser 200 is actuated at high speeds and pressures to generaterich foam in a short time. The actuator (not shown) moves the piston atapproximately 1.5 to 4 inches per second. When actuated at this highspeed, the dispenser 200 generates about 5 ml to about 19.5 ml of foamin about 0.2 to about 0.5 seconds. After pumping and before the air andliquid mixture flows through the foaming cartridge, the pressures in theair and liquid mixture range from about 4 psig to about 12 psig. Unlikethe foam cartridge 260, prior foam cartridges are unable to generaterich, uniform foam at these flow rates and pressures from foamableliquid containing alcohol.

FIG. 3 is an enlarged cross-sectional view of an exemplary foamcartridge 300 located in a foaming outlet 301 of foam dispenser 200. Thefoaming outlet 301 is simplified in FIG. 3 to more clearly show thecomponents of the foam cartridge 300. The foam cartridge 300 includes afirst foaming stage 310 and a second foaming stage 320 separated by agap 330. A mixture of air and liquid enters the foam cartridge 300 at aninlet 302 and is dispensed as rich foam from an outlet 304 moving in aflow direction 306. The first foaming stage 310 includes a coarse screen312, a sponge 314, and a fine screen 316. The second foaming stage 320includes a sponge 322 and a fine screen 324. The course screen 312 maybe filter media having about 40 to about 80 threads per inch. The finescreens 316, 324 may be filter media having about 80 to about 200threads per inch. The sponges 314, 322 may be porous media having about10 pores per inch to about 100 pores per inch.

Foam cartridge 300 provides an enhanced mixing of air and liquid and isparticularly useful for hard to foam liquids, such as liquids containingalcohol and those dispensed from high pressure, high velocity foampumps. Increased actuation speed decreases the time required to dispensea volume of foam into the hands of the user and increases the pressureand velocity of the air and liquid inside the pump. For example, a highdispenser speed of 1.5 to 4 inches per second results in pressures inthe air and liquid mixture ranging from about 4 psig to about 12 psig. Apump actuating at this speed can dispense about 5 ml to about 19.5 ml inabout 0.2 to about 0.5 seconds. Reducing the time to dispense foam isparticularly important in the medical profession, where the time ofmedical professionals is in high demand and comes at a considerablecost.

Each stage 310, 320 of the foam cartridge reduces the pressure of theair and liquid mixture exiting a foam pump, allowing more stable bubblesto be formed at the outlet 304 of the cartridge 300 when a foamableliquid containing alcohol is used. Reducing the pressure of the liquidand air mixture enhances formation of rich foam from an alcohol-basedfoamable liquid because bubbles formed in an alcohol-based foamableliquid have lower surface tension and therefore cannot maintain bubblesat the same pressures as bubbles formed in a soap-based liquid.

An air and liquid mixture entering the first foaming stage 310 passesthrough the coarse screen 312 to make the size of bubbles in the mixturemore uniform. The bubbles then pass through the sponge 314 where theyare continually reformed. The fine screen 316 reduces and refines thesize of the bubbles. The gap 330 between the first and second foamingstags 310, 320 allows bubbles exiting the fine screen 316 to fully formbefore entering the second stage 320. The gap 330 may be about 10% ofthe inner diameter of the foam cartridge 300, or may be between about10% to about 50% of the inner diameter of the foam cartridge 300. Thebubbles formed by the first foaming stage 310 flow through the secondfoaming stage 320 where they are continuously reformed by the sponge322. Lastly, the fine screen 324 ensures the bubbles exiting the foamcartridge 300 are small and uniform in size and are dispensed from thefoam cartridge 300 as rich foam.

While the above discussed embodiments show and describe wall mounted andabove counter mounted dispensers, the foam cartridge works very wellwith counter mount dispensers. An exemplary embodiment is shown anddescribed in U.S. Pat. No. 8,544,698 filed on Mar. 26, 2007 and entitledFoam Dispenser with Stationary Dispense Tube which is incorporatedherein in its entirety.

While the present invention has been illustrated by the description ofembodiments thereof, and while the embodiments have been described inconsiderable detail, it is not the intention of the applicants torestrict or in any way limit the scope of the appended claims to suchdetail. Additional advantages and modifications will readily appear tothose skilled in the art. Moreover, elements described with oneembodiment may be readily adapted for use with other embodiments.Therefore, the invention, in its broader aspects, is not limited to thespecific details, the representative apparatus and illustrative examplesshown and described. Accordingly, departures may be made from suchdetails without departing from the spirit or scope of the applicants'general inventive concept.

What is claimed is:
 1. A foam cartridge for a foam pump comprising: ahousing having an inner diameter; a first foaming stage disposed withinthe housing; the first foaming stage having at least two different typesof mix media; and a second foaming stage disposed within the housing;the second foaming stage having at least two different types of mixmedia; wherein the second foaming stage is spaced apart from the firstfoaming stage.
 2. The foam cartridge of claim 1 wherein: the housingcomprises a first portion and second portion; the first foaming stage isdisposed within the first portion and the second foaming stage isdisposed within the second portion.
 3. The foam cartridge of claim 1wherein the second foaming stage is spaced apart from the first foamingstage by about 10% of the inner diameter of the housing to about 50% ofthe inner diameter of the housing.
 4. The foam cartridge of claim 1wherein: the first foaming stage comprises at least two mix mediaselected from a coarse screen, a sponge, and a fine screen; and thesecond foaming stage comprises at least two mix media selected from acourse screen, a sponge, and a fine screen.
 5. The foam cartridge ofclaim 4 wherein the course screen has about 40 to about 80 threads perinch, the fine screen has about 80 to about 200 threads per inch, andthe sponge has about 10 to about 100 pores per inch.
 6. The foamcartridge of claim 1, wherein the mix media comprise at least one finescreen and one course screen.
 7. A refill unit for a foam dispensercomprising: a container for holding foamable liquid; a liquid pump; anair pump; an outlet nozzle; and a foam cartridge having: a first foamingstage having two or more different types of mix media; and a secondfoaming stage having two or more different types of mix media; whereinthe second foaming stage is spaced apart from the first foaming stage.8. The refill unit of claim 7 wherein the second foaming stage is spacedapart from the first foaming stage by about 10% of the outer diameter ofthe first foaming stage to about 50% of the outer diameter of the firstfoaming stage.
 9. The refill unit of claim 7 wherein: the first foamingstage comprises at least two mix media selected from a coarse screen, asponge, and a fine screen; and the second foaming stage comprises atleast two mix media selected from a course screen, a sponge, and a finescreen.
 10. A foam dispenser comprising: a housing; a refill unitinstalled in the dispenser, the refill unit comprising a container and apump secured to the container; wherein the pump includes an outletnozzle and a foaming cartridge, the foaming cartridge includes: a firstfoaming stage having two or more different types of mix media; and asecond foaming stage having two or more different types of mix media;wherein the second foaming stage is spaced apart from the first foamingstage.
 11. The foam dispenser of claim 10, wherein the dispenser is awall mounted dispenser.
 12. The foam dispenser of claim 10, wherein thedispenser is a counter mounted dispenser.
 13. A foam dispensing systemcomprising: a dispenser housing having an actuator for causing thedispensing of foam and a holder for receiving a refill unit; a refillunit having a container and a pump secured to the container, the refillunit further comprising: a first foaming stage having two or moredifferent types of mix media; and a second foaming stage having two ormore different types of mix media; wherein the second foaming stage isspaced apart from the first foaming stage.
 14. A foam cartridge for afoam pump comprising: a housing; a first mix media; a second mix media;and a third mix media; wherein at least two mix media are different. 15.The foam cartridge of claim 14, wherein the first and third mix mediaare screens.
 16. The foam cartridge of claim 14, wherein the second mixmedia is a sponge.
 17. The foam cartridge of claim 14, comprising afourth mix media.
 18. The foam cartridge of claim 17, wherein the fourthmix media is a sponge.
 19. The foam cartridge of claim 14, comprising afifth mix media.
 20. The foam cartridge of claim 19, wherein the fifthmix media is a screen.